Figure 7. Rate of Rev response element (RRE) modification by 100 nM M-chelate-Rev vs M-chelate complexes, in the presence of both 1 mM H₂O₂ and 1 mM ascorbate. The relative rates for each catalyst scale differently at higher concentrations, most likely as a result of differing higher-order reactivity with coreactants. For instance, at 10 µM catalyst/RNA, Fe-EDTA-Rev shows the highest rate of cleavage. Enhanced rates were observed for M-chelates attached to Rev for 100% of the species with above-background rates. The background rate with no complex was 0.28 ± 0.03 nM/min.